GO:0045931 positive regulation of mitotic cell cycle: Regulation, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0045931 (positive regulation of mitotic cell cycle) describes any process that activates or increases the rate or extent of progression through the mitotic cell cycle.
• MYC is a master transcriptional amplifier of mitotic cell cycle progression, driving expression of cyclins, CDKs, and E2F targets.
• PIN1 and APC/C(CDH1) act in reciprocal antagonism to control mitotic protein stability and cell cycle entry.
• Cytokinin and TOR signaling pathways positively regulate mitotic cell cycle progression in plants, linking nutrient and hormonal cues to division [2,5,8].
• Lysosomal changes during mitosis and CENP-A assembly are tightly coupled to positive regulation of mitotic progression [6,7].
• CRISPR knockout, point mutation, knock-in, and overexpression models are essential to dissect causal roles of genes in GO:0045931 [1,3].
Description
The Gene Ontology term GO:0045931, positive regulation of mitotic cell cycle, refers to any process that activates or increases the rate or extent of progression through the mitotic cell cycle. This term captures the positive arm of cell cycle control, encompassing transcriptional, post-translational, and signaling events that push cells through G1/S, G2/M, and mitotic exit. Understanding this process is fundamental to cancer biology, developmental biology, and regenerative medicine, because unchecked positive regulation leads to proliferation, while its failure causes growth arrest and genomic instability [1,3]. Mechanistically, positive regulation of the mitotic cell cycle is driven by oncogenic transcription factors such as MYC, which amplifies the expression of cyclins, CDKs, and E2F target genes. In parallel, the peptidyl-prolyl isomerase PIN1 and the ubiquitin ligase APC/C(CDH1) engage in reciprocal antagonism to govern the stability of mitotic proteins and the timing of cell cycle entry. In plants, cytokinin and TOR signaling provide external cues that positively regulate cell division, demonstrating the evolutionary conservation of this regulatory logic [2,5,8]. For researchers, GO:0045931 provides a structured framework to annotate genes and pathways that promote mitosis. It is widely used in functional genomics, CRISPR screening, and transcriptomic analyses to identify drivers of proliferation and to prioritize therapeutic targets in oncology and beyond [1,3,6].
positive regulation of mitotic cell cycle At A Glance
| GO ID | GO:0045931 |
|---|---|
| GO term | positive regulation of mitotic cell cycle |
| Ontology | biological_process |
| Definition | Any process that activates or increases the rate or extent of progression through the mitotic cell cycle. |
| Synonym | activation of progression through mitotic cell cycle; positive regulation of mitotic cell cycle progression; stimulation of progression through mitotic cell cycle; upregulation of progression through mitotic cell cycle |
| Major function | Drives cell division by promoting G1/S transition, G2/M transition, and mitotic progression through transcriptional, post-translational, and signaling mechanisms [1,3]. |
| Key regulators | MYC, PIN1, APC/C(CDH1), cytokinin signaling, TOR pathway [1,2,3,5,8]. |
| Disease relevance | Cancer, developmental disorders, and diseases of aberrant proliferation [1,3]. |
| Research methods | CRISPR knockout/knock-in, RNA-seq, proteomics, live-cell imaging, flow cytometry [1,3,6]. |
What Is GO:0045931?
In our own words, GO:0045931 (positive regulation of mitotic cell cycle) is a biological process that encompasses any molecular event or pathway that stimulates, accelerates, or sustains the progression of a cell through the mitotic cell cycle. It includes activation of cyclin-dependent kinases, transcriptional upregulation of mitotic genes, stabilization of mitotic proteins, and signaling cascades that remove inhibitory brakes on cell division [1,3].
Why Is positive regulation of mitotic cell cycle Important in Cell Biology?
Positive regulation of the mitotic cell cycle is central to understanding how cells decide to divide, how proliferation is sustained in cancer, and how external cues such as nutrients and hormones are integrated into cell cycle control [1,2,5]. Because many oncogenes and tumor suppressors converge on this process, it represents a rich source of therapeutic targets and biomarkers [1,3].
• MYC-driven transcriptional programs positively regulate the mitotic cell cycle and are deregulated in most human cancers.
• PIN1 and APC/C(CDH1) control the stability of mitotic proteins, and their imbalance promotes aberrant cell cycle entry.
• Cytokinin signaling positively regulates cell division in plants, with direct implications for crop growth and biomass [2,8].
• TOR signaling integrates nutrient availability with positive regulation of the mitotic cell cycle in plants and animals.
• Lysosomal dynamics during mitosis are linked to positive regulation of cell cycle progression and cellular quality control.
• CENP-A assembly and inheritance are tightly coordinated with mitotic progression, affecting chromosome stability.
• Dysregulation of positive regulators leads to uncontrolled proliferation, a hallmark of cancer [1,3].
• Loss of positive regulators causes growth arrest, relevant to developmental disorders and aging [1,3].
• CRISPR screens targeting positive regulators can identify synthetic lethal vulnerabilities in cancer [1,3].
• Understanding positive regulation informs strategies for regenerative medicine and tissue engineering [2,5].
What Happens During positive regulation of mitotic cell cycle?
Transcriptional activation of mitotic genes
In simple terms: The cell switches on a large set of genes that are needed to divide.
Positive regulation of the mitotic cell cycle begins with transcriptional programs that upregulate cyclins, CDKs, and E2F target genes. MYC acts as a global amplifier of these programs, binding to promoters of cell cycle genes and driving their expression. This transcriptional burst ensures that the machinery for DNA replication and mitosis is available in sufficient quantities.
Post-translational control of mitotic protein stability
In simple terms: Proteins that push the cell cycle forward are protected from degradation or actively stabilized.
The peptidyl-prolyl isomerase PIN1 and the ubiquitin ligase APC/C(CDH1) engage in reciprocal antagonism to control the stability of mitotic proteins. PIN1 stabilizes substrates that promote cell cycle entry, while APC/C(CDH1) targets them for degradation, and the balance between these activities determines whether cells commit to division.
Hormonal and nutrient signaling inputs
In simple terms: External signals like hormones and nutrients tell the cell it is a good time to divide.
In plants, cytokinin signaling activates a transcriptional cascade that positively regulates the mitotic cell cycle, promoting cell division in shoot and root meristems [2,8]. Similarly, the TOR pathway integrates nutrient status to promote cell cycle progression, linking growth cues to division.
Mitotic progression and organelle remodeling
In simple terms: During division, the cell reshapes its internal compartments to support the process.
Mitosis is accompanied by dynamic changes in lysosomes and other organelles, which support the metabolic demands of dividing cells. Additionally, the assembly and inheritance of CENP-A at centromeres are coordinated with mitotic progression to ensure faithful chromosome segregation.
Checkpoint override and commitment to division
In simple terms: The cell bypasses safety brakes to ensure division proceeds once started.
Positive regulation often involves overcoming inhibitory checkpoints. For example, MYC can override cell cycle arrest signals, and PIN1-mediated stabilization of mitotic proteins can bypass checkpoint controls, leading to accelerated division [1,3].
Key Genes Involved in GO:0045931 positive regulation of mitotic cell cycle
The following genes and proteins are central to positive regulation of the mitotic cell cycle, based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| MYC | Transcription factor amplifying expression of cyclins, CDKs, and E2F targets | Oncogene; target for cancer therapy and CRISPR knockout studies |
| PIN1 | Peptidyl-prolyl isomerase stabilizing mitotic proteins | Regulator of cell cycle entry; target for inhibitor development |
| APC/C(CDH1) | Ubiquitin ligase targeting mitotic proteins for degradation | Tumor suppressor context; balance with PIN1 determines cell cycle entry |
| CCND1 | Cyclin D1, promotes G1/S transition | Overexpressed in many cancers; CRISPR models for proliferation studies |
| CDK4 | Cyclin-dependent kinase 4, drives G1 progression | Target of CDK4/6 inhibitors; knockout models for cell cycle arrest |
| CDK6 | Cyclin-dependent kinase 6, drives G1 progression | Therapeutic target in cancer; CRISPR knockout to study proliferation |
| E2F1 | Transcription factor activating S-phase genes | Regulated by MYC; knockout causes cell cycle defects |
| CCNE1 | Cyclin E1, promotes G1/S transition | Amplified in cancers; overexpression models for proliferation |
| CDK2 | Cyclin-dependent kinase 2, drives S-phase entry | Target for cancer therapy; knockout studies |
| CDC25A | Phosphatase activating CDKs | Overexpressed in cancers; point mutation models for activity |
| CENP-A | Centromeric histone H3 variant, ensures chromosome segregation | Knock-in models to study centromere inheritance |
| TOR | Kinase integrating nutrient signals to promote cell cycle | Target of rapamycin; knockout models in plants and animals |
| Cytokinin receptors (AHK3, AHK4) | Hormone receptors activating cell division in plants [2,8] | Knockout models to study plant cell cycle [2,8] |
| Type-B ARR transcription factors | Mediate cytokinin transcriptional response [2,8] | Overexpression models to drive cell division [2,8] |
| LAMP1 | Lysosomal marker changed during mitosis | Imaging studies of organelle dynamics |
| SKP2 | F-box protein targeting p27 for degradation | Overexpressed in cancers; knockout causes cell cycle arrest |
| p27Kip1 (CDKN1B) | CDK inhibitor, negative regulator of cell cycle | Knockout models to study accelerated proliferation |
| p21Cip1 (CDKN1A) | CDK inhibitor, negative regulator | CRISPR knockout to study checkpoint control |
How Is positive regulation of mitotic cell cycle Regulated?
Positive regulation of the mitotic cell cycle is controlled at multiple levels. Transcriptionally, MYC and E2F family members amplify the expression of cell cycle genes. Post-translationally, PIN1 and APC/C(CDH1) reciprocally regulate the stability of mitotic proteins, with PIN1 stabilizing and APC/C(CDH1) degrading key substrates. In plants, cytokinin and TOR signaling pathways integrate hormonal and nutrient cues to promote cell division [2,5,8]. Additionally, lysosomal changes during mitosis and CENP-A assembly are coordinated with cell cycle progression [6,7].
positive regulation of mitotic cell cycle and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| MYC | Multiple cancers (Burkitt lymphoma, breast, lung) | Knockout and overexpression cell lines; CRISPR screens |
| PIN1 | Cancer, Alzheimer's disease | Point mutation knock-in to disrupt isomerase activity |
| CDK4 | Breast cancer, melanoma | Knockout for cell cycle arrest; point mutation for inhibitor resistance |
| CENP-A | Chromosome instability, developmental defects | Knock-in of tagged CENP-A for imaging |
| TOR | Cancer, metabolic disorders | Knockout in plant and mammalian cells |
Cancer
Deregulated positive regulation of the mitotic cell cycle is a hallmark of cancer. MYC amplification or overexpression drives uncontrolled proliferation in many tumor types. PIN1 is frequently overexpressed in cancers and its stabilization of mitotic proteins contributes to tumorigenesis. Targeting positive regulators such as CDK4/6 has proven clinically effective in breast cancer.
Developmental disorders
Mutations in genes that positively regulate the mitotic cell cycle can cause developmental defects due to impaired cell division. For example, loss of CENP-A function leads to chromosome segregation errors and developmental abnormalities.
Plant growth and crop yield
In plants, positive regulation of the mitotic cell cycle by cytokinin and TOR signaling determines organ size and yield. Manipulating these pathways through CRISPR can enhance biomass and stress tolerance [2,5,8].
From positive regulation of mitotic cell cycle-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is MYC required for mitotic cell cycle progression? | CRISPR knockout of MYC in cancer cell lines |
| Does PIN1 isomerase activity promote cell cycle entry? | Point mutation (C113S) knock-in of PIN1 |
| How does CENP-A assembly affect chromosome segregation? | Tagged knock-in of CENP-A with fluorescent protein |
| Can overexpression of cyclin D1 drive proliferation? | Overexpression of CCND1 in primary cells |
| What genes are essential for mitosis? | Genome-wide CRISPR library screening [1,3] |
| How does cytokinin signaling regulate plant cell division? | Knockout of cytokinin receptors in Arabidopsis [2,8] |
How to Study the positive regulation of mitotic cell cycle Process
| Method | What It Measures | Typical Application |
|---|---|---|
| RNA-seq | Transcriptional changes | Identify MYC/E2F target genes |
| Proteomics | Protein abundance and stability | Measure half-life of mitotic proteins |
| Live-cell imaging | Real-time mitotic progression | Track CENP-A or lysosome dynamics [6,7] |
| Flow cytometry | DNA content and cell cycle phases | Quantify proliferation after knockout |
| CRISPR screening | Essential genes for proliferation | Identify positive regulators [1,3] |
| Western blot | Protein expression and phosphorylation | Validate CDK activity |
| Immunofluorescence | Subcellular localization | Visualize mitotic structures |
Transcriptomic profiling
RNA-seq can identify genes whose expression is positively regulated during the mitotic cell cycle. Comparing proliferating vs. arrested cells reveals MYC and E2F target gene signatures.
Proteomic stability assays
Cycloheximide chase followed by western blot or mass spectrometry measures the half-life of mitotic proteins, revealing regulation by PIN1 and APC/C(CDH1).
Live-cell imaging
Fluorescently tagged proteins (e.g., CENP-A, LAMP1) allow real-time monitoring of mitotic progression and organelle dynamics [6,7].
Flow cytometry
DNA content analysis by flow cytometry quantifies cell cycle distribution and detects changes in proliferation upon genetic manipulation.
How CRISPR Can Be Used to Study GO:0045931 positive regulation of mitotic cell cycle
Knockout
CRISPR knockout of positive regulators such as MYC or CDK4 leads to cell cycle arrest, validating their essential roles. Knockout of PIN1 impairs cell cycle entry.
Point Mutation
Point mutations can dissect specific activities. For example, mutating the catalytic cysteine of PIN1 (C113S) abolishes isomerase activity and blocks its ability to promote cell cycle entry.
Knock-in
Knock-in of tagged CENP-A allows visualization of centromere assembly and inheritance during mitosis. Knock-in of mutant CDK4 can model inhibitor resistance.
Overexpression
Overexpression of cyclin D1 or MYC drives accelerated proliferation and is used to model oncogene-induced cell cycle entry.
How EDITGENE Supports positive regulation of mitotic cell cycle Research
Researchers studying positive regulation of mitotic cell cycle-related genes often need to determine whether a candidate gene is causally involved in promoting cell division. EDITGENE provides comprehensive CRISPR services to generate knockout, point mutation, knock-in, and overexpression cell models, as well as library screening and bioinformatics support.
Contact EDITGENE today to design your custom CRISPR model for positive regulation of mitotic cell cycle research.
Frequently Asked Questions About positive regulation of mitotic cell cycle
What is GO:0045931?
GO:0045931 is the Gene Ontology term for positive regulation of mitotic cell cycle, describing any process that activates or increases the rate of progression through mitosis.
What genes are involved in positive regulation of mitotic cell cycle?
Key genes include MYC, PIN1, APC/C(CDH1), CCND1, CDK4, CDK6, E2F1, and CENP-A, among others [1,3,7].
How does MYC regulate the mitotic cell cycle?
MYC acts as a transcriptional amplifier, driving expression of cyclins, CDKs, and E2F target genes to promote cell cycle progression.
What is the role of PIN1 in cell cycle entry?
PIN1 stabilizes mitotic proteins through prolyl isomerization, and its activity is antagonized by APC/C(CDH1) to control cell cycle entry.
How is the mitotic cell cycle regulated in plants?
Cytokinin and TOR signaling pathways positively regulate the plant cell cycle in response to hormones and nutrients [2,5,8].
What diseases are associated with dysregulated mitotic cell cycle?
Cancer is the most prominent, with MYC and PIN1 overexpression driving proliferation; developmental disorders can result from loss of positive regulators [1,3,7].
What methods are used to study positive regulation of mitotic cell cycle?
RNA-seq, proteomics, live-cell imaging, flow cytometry, and CRISPR screens are commonly used [1,3,6,7].
How can CRISPR help study GO:0045931?
CRISPR knockout, point mutation, knock-in, and overexpression models allow causal testing of genes in mitotic cell cycle regulation [1,3,7].
What is the relationship between lysosomes and mitosis?
Lysosomal changes occur during mitosis and are thought to support the metabolic demands of dividing cells.
Why is CENP-A important for mitosis?
CENP-A is a centromeric histone variant essential for chromosome segregation, and its assembly is coordinated with mitotic progression.
Conclusion
GO:0045931 (positive regulation of mitotic cell cycle) is a fundamental biological process that integrates transcriptional, post-translational, and signaling inputs to drive cell division. Its dysregulation underlies cancer and developmental disorders, making it a prime target for therapeutic intervention [1,3]. In plants, it controls growth and yield, with implications for agriculture [2,5,8]. CRISPR-based models are indispensable for dissecting the causal roles of individual genes within this process. EDITGENE offers a full suite of services to accelerate research on positive regulation of the mitotic cell cycle, from knockout to library screening and bioinformatics.
References
- 1. Bretones G et al.. 2015. Myc and cell cycle control.. Biochim Biophys Acta 1849(5):506-16 PMID: 24704206
- 2. Yang W et al.. 2021. Molecular mechanism of cytokinin-activated cell division in Arabidopsis.. Science 371(6536):1350-1355 PMID: 33632892
- 3. Ke S et al.. 2024. Reciprocal antagonism of PIN1-APC/C(CDH1) governs mitotic protein stability and cell cycle entry.. Nat Commun 15(1):3220 PMID: 38622115
- 5. Ahmad Z et al.. 2019. Cell cycle control by the target of rapamycin signalling pathway in plants.. J Exp Bot 70(8):2275-2284 PMID: 30918972
- 6. Stahl-Meyer J et al.. 2022. Lysosomal Changes in Mitosis.. Cells 11(5) PMID: 35269496
- 7. Rowley G et al.. 2025. A brief historical perspective on cell cycle control of CENP-A assembly and inheritance.. Chromosome Res 33(1):15 PMID: 40715876
- 8. Schaller GE et al.. 2014. Cytokinin and the cell cycle.. Curr Opin Plant Biol 21:7-15 PMID: 24994531
